From patchwork Mon Nov 6 15:48:09 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Uwe_Kleine-K=C3=B6nig?= X-Patchwork-Id: 13447150 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0A91DC4167D for ; Mon, 6 Nov 2023 15:48:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232202AbjKFPs6 (ORCPT ); Mon, 6 Nov 2023 10:48:58 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56810 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232591AbjKFPsz (ORCPT ); Mon, 6 Nov 2023 10:48:55 -0500 Received: from metis.whiteo.stw.pengutronix.de (metis.whiteo.stw.pengutronix.de [IPv6:2a0a:edc0:2:b01:1d::104]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id ED898191 for ; Mon, 6 Nov 2023 07:48:51 -0800 (PST) Received: from drehscheibe.grey.stw.pengutronix.de ([2a0a:edc0:0:c01:1d::a2]) by metis.whiteo.stw.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1r01qB-0007h8-T6; Mon, 06 Nov 2023 16:48:39 +0100 Received: from [2a0a:edc0:0:900:1d::77] (helo=ptz.office.stw.pengutronix.de) by drehscheibe.grey.stw.pengutronix.de with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1r01qA-0074pL-KW; Mon, 06 Nov 2023 16:48:38 +0100 Received: from ukl by ptz.office.stw.pengutronix.de with local (Exim 4.94.2) (envelope-from ) id 1r01qA-00Dn7o-B9; Mon, 06 Nov 2023 16:48:38 +0100 From: =?utf-8?q?Uwe_Kleine-K=C3=B6nig?= To: Wim Van Sebroeck , Guenter Roeck Cc: Nicolas Ferre , Alexandre Belloni , Claudiu Beznea , linux-watchdog@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kernel@pengutronix.de, linux-kbuild@vger.kernel.org Subject: [PATCH 1/5] watchdog: at91sam9: Stop using module_platform_driver_probe() Date: Mon, 6 Nov 2023 16:48:09 +0100 Message-ID: <20231106154807.3866712-2-u.kleine-koenig@pengutronix.de> X-Mailer: git-send-email 2.42.0.586.gbc5204569f7d.dirty In-Reply-To: <20231106154807.3866712-1-u.kleine-koenig@pengutronix.de> References: <20231106154807.3866712-1-u.kleine-koenig@pengutronix.de> MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=2464; i=u.kleine-koenig@pengutronix.de; h=from:subject; bh=6qCjLgRs8LjWcKpjoJFV/bKAmdWeXlVN/t58ixQNqro=; b=owEBbQGS/pANAwAKAY+A+1h9Ev5OAcsmYgBlSQq50rUzra2wa9jK/Iw4QnaVb7bB8WtVPVrkR zuaSr0MmoWJATMEAAEKAB0WIQQ/gaxpOnoeWYmt/tOPgPtYfRL+TgUCZUkKuQAKCRCPgPtYfRL+ TkkwB/97XYahEtj8N9mMvFKBMjHV5rsbBRZqUSuMy3WfbQOSeMx1TNnllYNNeb3BjY4titkJKRU u8MYE3UionZUlBkmJG/Fjushng/UmO3Vtc5S4NnO7bBbD2PoUkYEv2xUjQzgNTCCfjvz3mYPa+w DtHWzzltTvp+4WJJ0kfjV0z+MuFLuDKqWozOsOPa5xV4WCsS8UE45W97p5k/JoihULLerDvvveY Nh6sHCuZiALnu5nRB8YlplJqHfUjRSWLdUQDPyDeZRR2dPpDoohlIBdQ2PqQ48Tlsr1NBkA4U4I r6SCwD65Ky+fKj3th00+1nnFf2iox7ROf7+yq/CYVNOHeG0p X-Developer-Key: i=u.kleine-koenig@pengutronix.de; a=openpgp; fpr=0D2511F322BFAB1C1580266BE2DCDD9132669BD6 X-SA-Exim-Connect-IP: 2a0a:edc0:0:c01:1d::a2 X-SA-Exim-Mail-From: ukl@pengutronix.de X-SA-Exim-Scanned: No (on metis.whiteo.stw.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-kbuild@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org On today's platforms the benefit of platform_driver_probe() isn't that relevant any more. It allows to drop some code after booting (or module loading) for .probe() and discard the .remove() function completely if the driver is built-in. This typically saves a few 100k. The downside of platform_driver_probe() is that the driver cannot be bound and unbound at runtime which is ancient and also slightly complicates testing. There are also thoughts to deprecate platform_driver_probe() because it adds some complexity in the driver core for little gain. Also many drivers don't use it correctly. This driver for example misses to mark the driver struct with __refdata which is needed to suppress a (W=1) modpost warning: WARNING: modpost: drivers/watchdog/at91sam9_wdt: section mismatch in reference: at91wdt_driver+0x4 (section: .data) -> at91wdt_remove (section: .exit.text) Signed-off-by: Uwe Kleine-König Reviewed-by: Guenter Roeck Acked-by: Nicolas Ferre --- drivers/watchdog/at91sam9_wdt.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/drivers/watchdog/at91sam9_wdt.c b/drivers/watchdog/at91sam9_wdt.c index b111b28acb94..507adb12754d 100644 --- a/drivers/watchdog/at91sam9_wdt.c +++ b/drivers/watchdog/at91sam9_wdt.c @@ -324,7 +324,7 @@ static inline int of_at91wdt_init(struct device_node *np, struct at91wdt *wdt) } #endif -static int __init at91wdt_probe(struct platform_device *pdev) +static int at91wdt_probe(struct platform_device *pdev) { int err; struct at91wdt *wdt; @@ -372,7 +372,7 @@ static int __init at91wdt_probe(struct platform_device *pdev) return 0; } -static int __exit at91wdt_remove(struct platform_device *pdev) +static int at91wdt_remove(struct platform_device *pdev) { struct at91wdt *wdt = platform_get_drvdata(pdev); watchdog_unregister_device(&wdt->wdd); @@ -393,14 +393,14 @@ MODULE_DEVICE_TABLE(of, at91_wdt_dt_ids); #endif static struct platform_driver at91wdt_driver = { - .remove = __exit_p(at91wdt_remove), + .probe = at91wdt_probe, + .remove = at91wdt_remove, .driver = { .name = "at91_wdt", .of_match_table = of_match_ptr(at91_wdt_dt_ids), }, }; - -module_platform_driver_probe(at91wdt_driver, at91wdt_probe); +module_platform_driver(at91wdt_driver); MODULE_AUTHOR("Renaud CERRATO "); MODULE_DESCRIPTION("Watchdog driver for Atmel AT91SAM9x processors"); From patchwork Mon Nov 6 15:48:10 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Uwe_Kleine-K=C3=B6nig?= X-Patchwork-Id: 13447149 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5F1ADC4332F for ; Mon, 6 Nov 2023 15:48:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232192AbjKFPss (ORCPT ); Mon, 6 Nov 2023 10:48:48 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37886 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232213AbjKFPsq (ORCPT ); Mon, 6 Nov 2023 10:48:46 -0500 Received: from metis.whiteo.stw.pengutronix.de (metis.whiteo.stw.pengutronix.de [IPv6:2a0a:edc0:2:b01:1d::104]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0931B13E for ; Mon, 6 Nov 2023 07:48:44 -0800 (PST) Received: from drehscheibe.grey.stw.pengutronix.de ([2a0a:edc0:0:c01:1d::a2]) by metis.whiteo.stw.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1r01qB-0007h9-Ju; Mon, 06 Nov 2023 16:48:39 +0100 Received: from [2a0a:edc0:0:900:1d::77] (helo=ptz.office.stw.pengutronix.de) by drehscheibe.grey.stw.pengutronix.de with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1r01qA-0074pO-RQ; Mon, 06 Nov 2023 16:48:38 +0100 Received: from ukl by ptz.office.stw.pengutronix.de with local (Exim 4.94.2) (envelope-from ) id 1r01qA-00Dn7s-IA; Mon, 06 Nov 2023 16:48:38 +0100 From: =?utf-8?q?Uwe_Kleine-K=C3=B6nig?= To: Wim Van Sebroeck , Guenter Roeck Cc: linux-watchdog@vger.kernel.org, kernel@pengutronix.de, linux-kbuild@vger.kernel.org Subject: [PATCH 2/5] watchdog: txx9: Stop using module_platform_driver_probe() Date: Mon, 6 Nov 2023 16:48:10 +0100 Message-ID: <20231106154807.3866712-3-u.kleine-koenig@pengutronix.de> X-Mailer: git-send-email 2.42.0.586.gbc5204569f7d.dirty In-Reply-To: <20231106154807.3866712-1-u.kleine-koenig@pengutronix.de> References: <20231106154807.3866712-1-u.kleine-koenig@pengutronix.de> MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=2289; i=u.kleine-koenig@pengutronix.de; h=from:subject; bh=Kz0fRs6Kvl4uYaSittIqsKRgAcv2hRtW689WI81wO08=; b=owEBbQGS/pANAwAKAY+A+1h9Ev5OAcsmYgBlSQq6ptl/HF7aDDKiZ+IYulAfXPSV2Z2EIkpBW HWwch1IF4iJATMEAAEKAB0WIQQ/gaxpOnoeWYmt/tOPgPtYfRL+TgUCZUkKugAKCRCPgPtYfRL+ TqdpCACf4KSWthH8R50+QUU5LJalugRsnD1MUifGJV8ekW4wGLtyFs3yWlFaArkjG/+ueronsb7 pEkhgjhqv9j1IJNqO75Yb6efSWc53U3e3D5f39DFrlMj8TMISpuK/Kzkp8vIhrClD1BseUH9FpW dnJceGeOPuhzY8FbuPb91OvC3Ve0BHDBMLPQZLwlmeAZW/IME/pLp5MNM0of+sXu1KoDsra4/OF SDzR/CZpkk43DwpQoccLalRAjmyKC0jNDsf3OdxaJDjBoHl37UOL4fpE4ZOzo8w5YaRDuzrMsBo +/jwAtOBcixQws0E5JxzptBdN7NeHlOl6wrvINiSdIpNd7zE X-Developer-Key: i=u.kleine-koenig@pengutronix.de; a=openpgp; fpr=0D2511F322BFAB1C1580266BE2DCDD9132669BD6 X-SA-Exim-Connect-IP: 2a0a:edc0:0:c01:1d::a2 X-SA-Exim-Mail-From: ukl@pengutronix.de X-SA-Exim-Scanned: No (on metis.whiteo.stw.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-kbuild@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org On today's platforms the benefit of platform_driver_probe() isn't that relevant any more. It allows to drop some code after booting (or module loading) for .probe() and discard the .remove() function completely if the driver is built-in. This typically saves a few 100k. The downside of platform_driver_probe() is that the driver cannot be bound and unbound at runtime which is ancient and also slightly complicates testing. There are also thoughts to deprecate platform_driver_probe() because it adds some complexity in the driver core for little gain. Also many drivers don't use it correctly. This driver for example misses to mark the driver struct with __refdata which is needed to suppress a (W=1) modpost warning: WARNING: modpost: drivers/watchdog/txx9wdt: section mismatch in reference: txx9wdt_driver+0x4 (section: .data) -> txx9wdt_remove (section: .exit.text) Signed-off-by: Uwe Kleine-König Reviewed-by: Guenter Roeck --- drivers/watchdog/txx9wdt.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/drivers/watchdog/txx9wdt.c b/drivers/watchdog/txx9wdt.c index 89a54b6645bd..f900c519ed63 100644 --- a/drivers/watchdog/txx9wdt.c +++ b/drivers/watchdog/txx9wdt.c @@ -98,7 +98,7 @@ static struct watchdog_device txx9wdt = { .ops = &txx9wdt_ops, }; -static int __init txx9wdt_probe(struct platform_device *dev) +static int txx9wdt_probe(struct platform_device *dev) { int ret; @@ -145,7 +145,7 @@ static int __init txx9wdt_probe(struct platform_device *dev) return ret; } -static int __exit txx9wdt_remove(struct platform_device *dev) +static int txx9wdt_remove(struct platform_device *dev) { watchdog_unregister_device(&txx9wdt); clk_disable_unprepare(txx9_imclk); @@ -159,14 +159,14 @@ static void txx9wdt_shutdown(struct platform_device *dev) } static struct platform_driver txx9wdt_driver = { - .remove = __exit_p(txx9wdt_remove), + .probe = txx9wdt_probe, + .remove = txx9wdt_remove, .shutdown = txx9wdt_shutdown, .driver = { .name = "txx9wdt", }, }; - -module_platform_driver_probe(txx9wdt_driver, txx9wdt_probe); +module_platform_driver(txx9wdt_driver); MODULE_DESCRIPTION("TXx9 Watchdog Driver"); MODULE_LICENSE("GPL");